Team:Freiburg Bioware/Safety
From 2010.igem.org
Biosafety
Def: "biosafety measures aim to prevent the unintentional exposure to pathogens and toxins, or their accidental releas" 1
Risk assessment for our Adeno-associated virus based system
For the usage in the Federal Republic of Germany the Central Commission for Biological Security (ZKBS) released three legally binding Risk Assessment for the Adeno-associated Virus
26,
27,
28. The risk assessment in other countries could deviate from this decision, so please inform you about the legal regulation for the AAV in your country before using the Virus Construction Kit.
The classification in Biological Safety Level (BSL) is:
This general classification has to be rechecked when:
For Viral Vectors that package a Vector plasmid that only contains the viral Inverted Terminal Repeats (ITRs) and provide the genes for the Rep and Cap genes in Trans as it is the case for our system: These Viral Vectors are classified as BSLI if the following conditions are fullfilled:
We also investigated the legal regulations on AAV-2 Viral Vector systems in the United States. The guidelines of the National Institutes of Health (NIH) classifyes in the Appendix B 32 AAV-2 Vector Systems as Risk Group 1 (RG1) Agents that can be treated under BSL 1.
adeno- associated virus (AAV) types 1 through 4; and recombinant AAV constructs, in which the transgene does not encode either a potentially tumorigenic gene product or a toxin molecule and are produced in the absence of a helper virus.
General specifications of the Adeno-associated Virus 2 (AAV-2):
Legal regularisation in the Federal Republic of Germany
In Germany all working that includes recombinant DNA technologies is regulated by the Gesetz zur Regelung der Gentechnik. This law regulates general aspects arising from the life sciences and refers for more precise interpretations in §4 to the Zentrale Kommission für die Biologische Sicherheit. The ZKBS is a commission composed of 20 technical experts that releases yearly statements to actual issues of biosafety. So far the ZKBS released three stratements affecting the work with Adeno-associated viral systems 26, 27, 28. These documents were used to assess the dangers that could arise from our project to team members and the enviroment.
At the Albert-Ludwigs-University Freiburg for all concerns of security the Stabsstelle Sicherheit is responsible and to contact if questions arise. Especially for questions of biological security Dr. Petra Markmeyer-Pieles is cognizant. We contacted her a first time befor the begin of our project in March when it was clear that the Adeno-associated Virus (AAV-2) was chosen as the topic of our project. At that time she proposed to do the cloning in the AAV-2 that is for sure to handle under biological security level 1 and to prepare everything for work under biological security level 2 to satisfy the precaution principle. The precaution principle was realized and all viral vectors that contained a modified capsid were handled under SII conditions until proven harmless. In August the planing of the project was completed, summarized in an Biosafety application30 and handed to the department for biological security who approve the application in an official BSL1 confirmation31official BSL1 confirmation for our project.
Risk management
Our project was designed in a way that it avoids any serious safety issues as far as possible. When working with infectious particles a minimal risk for the researcher is allways present. This risk was minimized by restricting the transduced genes to fluorescent proteins and prodrug convertases that are already proven not to harm human cells in the absece of the corresponding prodrug. A potential danger for the public or the environment was minimized as much as possible by following strictly the rules of Good Laboratory Practice (GLP) and the abdication of using randomized insertions in the capsid and of replication potent viruses. Minimizing the risk for team members and the society was was allways one of the major concerns, especially because worries about undergraduate students manipulating a virus could arise. The security concept will be explained by quoting and explaining the six guiding principles for safe manipulation of Gene Manipulated Organisms (GMOs) as summarized in Kimman et al. ; 200818.
Several composite parts that were assembled by our Team this year are alone capable of producing infectious viral particles when transduced together with a vector plasmid and a helper plasmid into AAV-293 cells. These special cells provide the adenoviral gene E1 stabily integrated in trans. These cells are not provided in the Virus Construction Kit nor availible in the Parts Registry and have to purchased from other laboratories or a commercial supplyer. For this reason we estimate the risk of a accidental transformation of AAV-293 cells with all three plasmids for negligible. Nevertheless we considered it useful to mark every BioBrick or Composite Part in the Registry that contributes to the production or is capable of producing viral vectors when transformed under the previously mentioned conditions.
psychological research into the concept of "identity-driven decision-making" (Torpman,2004) 19
Every grout has a set of norms: a code of conduct about what is acceptable beahviour (Jaques, 2004] 19
Trade-off between potential misuse and promising medical progress
In principle each research-project that bears any risks for engaged researchers, mankind or the environment should be treated under the precautionary principle as proposed 11: "treat synthetic microorganisms as dangerous until proven harmless".
This would mean to work on such synthetic DNA containing Bio Bricks at least under Biological security levels two.
Additional to this secure working environment the system itself can be optimized according to biosafety aspects, means to reduce it's viability outside the laboratory. This aim can be approached by reducing the systems ability to evolve, proliferate and interact with it's environment. A common method to achieve this goal is to engineer microorganisms in a way that they depend on nutrients that can't be found in the environment in sufficient amount.
Biosecurity
The malignant use of biological agents in history
The misuse of biological agent as weapons in warfare is a fear spreading companion in the history of mankind, ranging from the well-poisoners in prehistoric times to bio-terrorists present days. The following brakt intends to give a short outline of the major events22:
''"develop, produce, stockpile or otherwise acquire or retain: ... Microbial or other biological agents, or toxins whatever their origin or method of production, of types and in wantities that have no justification for prophylactic, protective or other peaceful purpose..." ''3
Broad avilibility of knowledge
For the overwhelming majority this open availibility is absolutely desirely but on the other hand there are also examples of research results that bear a very high risk to be misused.
Following we present the three most controversial discussed publications that could also be read as a "How to create your own bioweapon".
Mousepox Virus in Australien
The Australian research group around Jackson et al. ; 2001 16inserted the coding region of the IL-4 gne into the genome of mousepox. They hoped to create a virus that sterilizes mice and thus provides a means for pest control. Contrarely to their expectations they had created a superstrain that killed even naturally resistent mice and mice that had been vaccinated against normal mousepox. This discovery could potentially be used to make smallpox resistant to potential vaccines.
Synthesis of a Polio Virus
At the State University of New York
"made the virus to send a warning that terrorists might be able to make biological weapons without obtaining a natrual virus"17
Reconstitution of the Spanish Flu
At the Center for Disease Control and Prevention (CDC) the group around Tumpey et al. ; 200524 published that they had sequenced and recreated the pandemic Spanish Flu Virus of 1918 which killed 20-50 million people. The publication of the sequence provoked several very different responses that can only be partially be quoted here. The controversial noticed outrider of the Synthetic Biology Craig Venter seen in the new virus
"the first true Juressic Parc scenario" 2The Institute Professor at the MIT Philip A. Sharp supported the publication because he:
"belive[s] that allowing the publication of this information was the correct decision in terms of both national security and public health" 12Wheras v. Bubnoff; 200525 critisizes the CDS for it's careless regulations for the shipment of viruses and the willingness to propagate highly virulent viruses. This causes in his opinion the risk of possible accidents resulting in the release of the virus to the environment.
Broad avilibility of material
Szenarios of attack
Conclusion
For sure there is allway the possibility that knowledge to produce transgene viral vectors could be used to produce bioweapons. Therefor it was important for us to use a system that does not bear the risk that someone could use it for evil purpose. In the case of the Adeno-associated virus the very limited packaging capacity is the major reason that excludes it from the list of agents that could realistically be used for the pruduction of bioweapons. Even a fully replication potent AAV will depend on the coninfection of a helpervirus and is therefore not suitable for a fast propagation in an population. Additional to this point we concentrated our project on the retargeting of the virus - means to make the broad tropismn more narrow and to decrease the transduction efficiency in the most cases. This modification is usually mainly required for medical purposes. Also we did neither investigate possibilities to shield the vector from the immune system of potential host nor ways to bypass an existing immunity.
used